Mold-drying stove.



P. MONGEN. MOLD.DRYING STOVE. APPLIGATIGN FILED A'UG.13,|1910.

- Patented May 21, 1912.

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P. MON GEN MOLD DRYING STOVE. APPLICATION FILED AUG. 13, 1910.

Patented May 21, 1912.

f For dry ng ed to the molds;

. noun-DRYING s'rovn.

Specificationof Letters ratent.

To all may I "Be it'known that I, Pam. MONGEN, a subject of the Emperor of Germany, residing at. 72 Kalkerstrasse, Miilheim-on-the-Rhine,

Germany, have invented newand useful Improvements in Mold Drying Stoves, of which the following is a specification.

portable dryingovens are used which consist ofa furnaceand a chamber for heating the air, in these ovens acurrent of com-- blue flames are produced'inside thefurnace it reaches the molds,-by more. fresh air enescape through dry-air flue respectively and reaching evenas far as the dry-airfiue,

or that theair is-overheated and is, too greatly mixed with the furnace gases before tering from above into the furnace than can the chimney-flue and the so that the air is pressed and will. strike] backiinto thefurnace. .In both instances the molds are likely to. be burned, to crack or flake ofi. Itis, in-

deed, possible to control the temperature and thev air-supply by means of-closures and dampers,so t at a burning of'the'mold is avoided; that is, a constant, careful attendance by a skilled, reliable staff, which it will very rarely be possible to find.

' It has been proposed to conduct-- the com-' ressed" air, heated in separate" heatingchambers to the molds through a flue leadingi downward on the side of the oven,and to etinto this hot-air flue like a branch-pipe, so

air and so conduct them to the molds. This result is, however, not obtained, as the current of compressed air will not carry along the furnace gases, which are under a lower pressure, if t e width of the flue remains the same, but will partly blow them out through both furnace and grate. But evenin case the intended result should be obtained, also so arranged-ovens would cause the molds to be burned, as there is no supply of cold air whatever. The known types of ovens further have the disadvantage, that when air is blown into and through the furnace chamher fine ashes and dust will enter into the the. molds in foundries small whereupon it is conduct-- 1 is the. body the 'waste-gasfl'ue of the furnace enter Amati... filed au ust is, 1910. Serial No. 571,077.

mold, so that it will become impossible to STATES: 5

mm. mona'nn; or' mtirnnm-oa-rnmnnmnfG RMANY.

Patented May 2 L1912.

feed fresh 'fuel into the furnace during the I drying process, andit will be necessary to remove with much trouble the ashes in small quantities after the fire has burned "out, as

it will not be possible toempty the whole time, as the space beneath the be closable and partlyalso congrate at a same must .tains thecoinpressed-air pipes, the damperguide walls and the like.

The present invention removes all thedif- I ficulties and troubles, mentioned above.

' According to the present met-hodhotair and furnace-gases are sucked off by meansof a current of cold compressed air, in given,-

constant quantities and mixed with the cold compressed air-at a g ven ratio, so that the mixtureconducted. to themolds will have a given limited and permissible .;maximum temperature, whereassimultaneously and at thesame ratio ashot airand gasesfrom the furnace are sucked "off, fresh air is again sucked through the gratei-nt'o the furnace,

so that the combustion is maintained in a uniform manner and the hot air and turn ce gases sucked off from above are *again eplaced.

The constructional form of an apparatus for earv rying out this method. however, only possible by Figure 1 is a vertical Fig.v 2 is a front of the oven, whichv rests with base 2 onthe girders 3 and has a grate 4. Below the grate is an air chamber 5, above the same the furnace chamber 6. The horizontal waste gas flue 7 leads from the furnace chamber 6; into the upperenlarged end 10 of a dry-air flue 9, into which it accompanying drawing exemplifies a longitudinal section. elevation. Fig. 3 is a plan.

enters from the side. Into theenlarged end 10 of the dry air flue 9.leads also from above the compressed air pipe, in the present instance the delivery nozzle 11 of a blower 12, which enters vertically and concentrically into theiflue 9. The dry-air flue 9 is fitted at its lower end with a mouth piece 8, and has a greater width than the nozzle 11.

For practical reasons the blower 12with the motor 13 have been mounted on the top .of the oven-body 1. is provided for charging the fuel on to the grate 4. rising is shut down after work, and the hot air'is to be removed by opening the door 14.. When the blower 12' is started, after the The charging door 1 1x month piece 8 of the dry-air flue 9 has been for long blueflames to be produced, for the air to be pressed and strike back into the furnace chamber 6 in consequence of an insnificient supply of fresh air from below, and that the drying air is overheated; By determining from the very first the, proper shape'and degree ofxthe enlargement 10- of the flue '9 and the ratio between its area and that of the compressed-air supply pipe'it will'be possible to give the warm mixture of air and gas produced in thedry-air flue 9 a certain maximum temperature which it will'not affect the mold, and tO maintain the air and gas mixture permanently at such temperature. The invention furthermore affords the following advantages. Fresh fuel can be charged into the furnace during the drying process without the compressed-air pipe having to be shut off, as no hot-air,"carrying smoke and fine ashes with it, willbe forcedout when the doonl is, openedifor such purpose. Asdthe dry air is carried along by the cold air entering in a permanently constant quantity and a slow current, so that a uniform suction is produced over the Whole grate area, it is out of question, that ashes and the like can get into .the mold and stick in places which are later on no moregaccesbase 2'01 close above it.

sible. The separate air-chamber 5 below the grate 4,-which hitherto had to be of a considerable height for allowing of a supply of a part of the air from the blower and for admitting of the pipes, closure andregulating" dampers being arranged here, may be dispensed with in the arrangement according to the present invention as thegrate 4may be placed immediately in the level of the The oven [can therefore be constructed lower than hitherto,

namelyby the height ofthe under-grate air chamber 5, which is nevertheless shown in the drawing. This reduction'in height will amount to about 15 centimeters or 6 inches.

In consequence thereof and also by the fact that no special blast distribu ting conduits to the grate and the necessary dampers are required thefurnace may be made both of a j smaller size and at a lower cost.

. I claim:

A mold drying apparatus comprising in 4 combination, a combustion a chamber provided with a grate and having an open air inlet to the grate from below, a vertically disposed air conduit having an enlarged upper end communicating with'said chamber at a point above the grate, means connectingthe discharge of said conduit with the runner of the mold, andmeans projecting into the upper enlarged end of said conduit and forcing the air downwardly therethrough into the 'mold thereby inducing a mixture with such air of the products of combustion from said chamber.

In testimony whereof I hereto afiix my signature in presence of two witnesses.

' PAUL MONGEN. I

I Witnesses: I

\VALTER- MONGEN, r OSCAR DEPNER. 

